Wednesday, May 9, 2012

Reducing e. coli Contamination

There's a report at Science Daily that talks about research by a "Cand.agric. Sigrun J. Hauge defended her doctoral research on 2nd May
2012 at The Norwegian School of Veterinary Science (NVH) with a thesis
entitled "Hygienic impact of measures related to unclean cattle and
sheep at farm level and in the abattoir."" The article goes on to detail Sigrun's testing of a "hot water pasteurization" process for destroying e. coli on lamb carcases. It is an interesting read (a copy follows), but its predicated on treating animals as industrial inputs. Stop doing that and meeat will become more expensive, better, and better for us.

ScienceDaily (May 4, 2012) — Following the E. coli
case in Norway in 2006, when 17 people fell ill and one child died
after eating mutton sausages, the meat industry introduced a number of
measures in order to reduce the risk of food poisoning from meat. Clean
animals and good hygiene during slaughtering are essential preconditions
for food safety.

Sigrun J. Hauge has studied the effect of the measures implemented on
farms and in slaughterhouses. The aim of the project "Uncontaminated
Carcasses" was to uncover data that would help to improve the hygienic
quality of meat from cattle and sheep by means of cleaner animals and
efficient ways of slaughtering high-risk animals.E. coli is a commonly occurring bacterium in the digestive
tract of humans, animals and birds. Just a few strains are pathogenic
and can cause diarrhea and kidney failure, particularly in children. The
bacteria die at temperatures over 60-70 °C and are therefore normally
eliminated by boiling and roasting. Hauge has shown that a new, rapid
enzymatic method for detecting E. coli is equally as reliable
as the traditional method of growing bacteria culture. This new method
is therefore suitable for monitoring E. coli in abattoirs.High-risk animals
Slaughterhouses have systems for categorizing animals according to
how dirty they are. Around 3-5% of the animals that arrive at abattoirs
are so soiled that they are categorised as high-risk. Every year,
deductions in the price of meat due to dirty animals amount to over 9
million Norwegian kroners. Soiled slaughter can pose a risk to food
safety because faeces on hides/wool, intestines, knives and the hands of
the butchers can be transferred to the meat during the slaughter
process. Hauge studied the factors affecting the cleanliness of animals
on farms and how clean or soiled hide affects the contamination of
skinned carcasses. Her experiments confirmed that meat from dirty cattle
has more E. coli than meat from clean cattle.
Sheep farmers are also subjected to price reductions for dirty and
unshorn animals. Hauge's research showed that the surface of meat from
shorn sheep has less E. coli than that of unshorn sheep
immediately after skinning and that the point in time that the sheep are
shorn before slaughtering is also significant when it comes to the
amount of bacteria immediately after skinning. But towards the end of
the slaughtering process, all the meat had equal amounts of E. coli on its surface, regardless of when the sheep were shorn.
Dirty and unshorn animals are considered a high risk. They are
treated in separate product streams in the slaughterhouses and their
meat is not used for raw products such as minced meat and cured meat,
but for products that are heat treated before sale (such as sausages and
meatballs etc.)99.5% reduction of E. coli
Meat from lambs was hosed with water at 82 °C for 8 seconds in an
enclosed "shower" -- so-called hot water pasteurization -- before it was
cooled. This treatment reduced the amount of E. coli on carcasses by 99.5%. After 5 days of cooling, no further E. coli
were found on the meat. The recycled water in the shower was of a good
microbiological, chemical and physical quality. Immediately after
pasteurization, the meat was rather pale, but it regained its normal
colour after being cooled for 24 hours.
Hot water pasteurisation is not generally accepted as a hygiene
measure in Norway and the EU and the Norwegian Food Safety Authority
would have to give its approval, if the method is to be used at
slaughterhouses. Hot water pasteurisation will obviate the need for
separate product streams in abattoirs for high-risk sheep.
Cand.agric. Sigrun J. Hauge defended her doctoral research on 2nd May
2012 at The Norwegian School of Veterinary Science (NVH) with a thesis
entitled "Hygienic impact of measures related to unclean cattle and
sheep at farm level and in the abattoir."

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Hitch-hiked across Canada in the mid-seventies, changing, in the process, from an Albertan into a Canadian. Entered post-secondary studies at Grant McEwan College in Edmonton, moving over to the U of Alberta a year later to read English Lit. Friends invited me out for a visit to Victoria, and a week later I had a job, place to live, and was enrolled at UVic. Married two years later, we had twins (a boy, a girl, and a vasectomy), moved back to Alberta where we ran an over-educated New Agriculture farm for fourteen years. After the kids moved out, moved back to Victoria where we discovered sea kayaking. Live quietly, trying to pursue a life of voluntary simplicity, although we occasionally fail to live up to our own ideals. Still married, 28 years later, to the same person--and quite happy about it. Currently working on a book about Canadian food security issues.